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Abstract:

Systems and methods for processing and sorting a municipal solid waste
stream are described herein. A system can include a processing sub-system
configured to receive a municipal solid waste stream and to remove the
non-processable waste, a processing apparatus configured and disposed to
receive constituents of the municipal solid waste stream from the
processing sub-system and reduce the size of the constituents of the
waste stream to an average particle size of less than about 3/4 inch, and
separators configured to sort the waste stream into constituents based on
density.

Claims:

1. A system for processing and sorting a municipal solid waste stream,
the system comprising: a processing sub-system configured to receive a
municipal solid waste stream and to remove the non-processable waste; a
processing apparatus configured and disposed to receive constituents of
the municipal solid waste stream from the processing sub-system and
reduce the size of the constituents of the waste stream to an average
particle size of less than about 3/4 inch; a first separator configured
and disposed to receive the constituents of the waste stream from the
processing apparatus and to separate and remove waste constituents of a
first type having a bulk density greater than about 15 lb/ft3; and a
second separator configured and disposed to receive the constituents of
the waste stream having a bulk density less than about 15 lb/ft3
from the first separator and to separate and remove waste constituents of
a second type having a bulk density greater than about 4 lb/ft.sup.3.

2. The system of claim 1, further comprising: a third separator
configured and disposed to receive the constituents of the waste stream
having a bulk density less than about 4 lb/ft3 from the second
separator and to separate and remove waste constituents of a third type
having a bulk density greater than about 1 lb/ft.sup.3.

3. The system of claim 1, wherein the processing sub-system includes a
shredder configured to reduce the size of the constituents of the waste
stream to be less than about 4 inches.

4. The system of claim 3, wherein the shredder is configured to reduce
the size of the constituents of the waste stream to be less than about 1
inch.

5. The system of claim 1, wherein the processing sub-system includes a
density separator configured to separate and remove the non-processable
waste.

6. (canceled)

7. (canceled)

8. The system of claim 1, wherein the processing apparatus is a shredder.

9. The system of claim 8, wherein the shredder is configured to reduce
the size of the constituents of the waste stream to be less than about
1/2 inch.

10-15. (canceled)

16. The system of claim 1, wherein the waste constituents of the first
type are substantially all hard plastic.

17. The system of claim 1, wherein the waste constituents of the second
type are substantially all fiber.

18. The system of claim 2, wherein the waste constituents of the third
type are substantially all soft plastic.

19. A system, comprising: a first shredder configured to receive a
municipal solid waste stream and reduce the size of constituents of the
waste stream to be less than about 4 inches; a first density separator
configured and disposed to receive the shredded waste stream from the
first shredder and to separate and remove the non-processable waste; a
second shredder configured and disposed to receive the processable waste
from the first density separator and to reduce the size of constituents
of the processable waste to be less than about 1/2 inch; a second density
separator configured and disposed to receive the processable waste from
the second shredder and to separate and remove the hard plastic material;
and a third density separator configured and disposed to receive the
non-hard plastic material from the second density separator and to
separate and remove the fiber material.

20. The system of claim 19, further comprising: a fourth density
separator configured and disposed to receive the non-fiber material from
the third density separator and to separate and remove the soft plastic
material.

21. The system of claim 19, wherein the first shredder is configured to
reduce the size of the constituents of the waste stream to be less than
about 1 inch.

22. (canceled)

23. The system of claim 19, wherein the second shredder is configured to
reduce the size of the constituents of the processable waste to be less
than about 3/8 inch.

24. (canceled)

25. The system of claim 19, wherein the hard plastic has a bulk density
in the range of about 15 lb/ft3 to about 25 lb/ft.sup.3.

26. The system of claim 19, wherein the fiber has a bulk density in the
range of about 4 lb/ft3 to about 15 lb/ft.sup.3.

27. The system of claim 20, wherein the soft plastic has a bulk density
in the range of about 1 lb/ft3 to about 4 lb/ft.sup.3.

28. The system of claim 19, wherein at least one of the first, second and
third density separator is a cyclone separator.

29. The system of claim 19, wherein at least one of the first, second and
third density separator is a fluidized bed separator.

30-40. (canceled)

41. The system of claim 5, wherein the density separator is a cyclone
separator.

42. The system of claim 5, wherein the density separator is a fluidized
bed separator.

43. The system of claim 9, wherein the shredder is configured to reduce
the size of the constituents of the waste stream to be less than about
3/8 inch.

44. The system of claim 10, wherein the shredder is configured to reduce
the size of the constituents of the waste stream to be less than about
1/4 inch.

45. The system of claim 1, wherein the first separator is a cyclone
separator.

46. The system of claim 1, wherein the first separator is a fluidized bed
separator.

47. The system of claim 1, wherein the second separator is a cyclone
separator.

48. The system of claim 1, wherein the second separator is a fluidized
bed separator.

49. The system of claim 21, wherein the first shredder is configured to
reduce the size of the constituents of the waste stream to be less than
about 1/2 inch.

50. The system of claim 23, wherein the second shredder is configured to
reduce the size of the constituents of the processable waste to be less
than about 1/4 inch.

Description:

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to and the benefit of U.S.
Provisional Application Ser. No. 61/493,071, entitled "Systems, Methods
and Processes for Granulating Heterogeneous Waste Streams for Engineered
Fuel Feedstock Production," filed Jun. 3, 2011, and U.S. Provisional
Application Ser. No. 61/645,931, entitled "Systems and Methods for
Producing Engineered Fuel Feed Stocks From Waste Material," filed May 11,
2012, each of which is incorporated herein by reference in its entirety.

[0002] This application is also related to U.S. Patent Application
Attorney Docket No. RECM-022/03US 314670-2111, entitled "Systems and
Methods for Producing Engineered Fuel Feed Stocks from Waste Material,"
filed Jun. 1, 2012, the disclosure of which is incorporated herein in its
entirety.

BACKGROUND

[0003] The disclosure relates to alternative fuels, chemicals, and fuel
feed stocks. In particular, the disclosure relates to systems and methods
for producing an engineered fuel feed stock having additives to control
emissions, prevent corrosion, and/or improve operational performance
during combustion or gasification applications. The feed stock described
herein includes at least one component of processed solid waste, an
additive, and optionally other components.

[0004] Sources of fossil fuels useful for heating, transportation, and the
production of chemicals as well as petrochemicals are becoming
increasingly scarce and costly. Industries such as those producing energy
and petrochemicals are actively searching for cost-effective engineered
fuel feed stock alternatives for use in generating those products and
many others. Additionally, due to the ever increasing costs of fossil
fuels, transportation costs for moving engineered fuel feed stocks for
production of energy and petrochemicals is rapidly escalating.

[0005] These energy and petrochemical producing industries, and others,
have relied on the use of fossil fuels, such as coal and oil and natural
gas, for use in combustion and gasification processes for the production
of energy, for heating and electricity, and the generation of synthesis
gas used for the downstream production of chemicals and liquid fuels, as
well as an energy source for turbines.

[0006] One potentially significant source of feed stock for production of
an engineered fuel is solid waste. Solid waste, such as municipal solid
waste (MSW), is typically disposed of in landfills or used in combustion
processes to generate heat and/or steam for use in turbines. The
drawbacks accompanying combustion include the production of pollutants
such as nitrogen oxides, sulfur oxides, particulates and products of
chlorine that are damaging to the environment.

[0007] Thus, there is a need for alternative fuels that burn efficiently
and cleanly and that can be used for the production of energy and/or
chemicals. There is at the same time a need for waste management systems
that implement methods for reducing green house gas emissions of waste by
utilizing such wastes. In particular, there is a need for improved
systems and methods for sorting waste material and reclaiming a resource
value from components of the waste material. By harnessing and using the
energy content contained in waste, it is possible to reduce green house
gas emissions and/or otherwise reduce emissions generated during the
processing of wastes thereby effectively using the waste generated by
commercial and residential consumers.

SUMMARY

[0008] Systems and methods for processing and sorting a municipal solid
waste stream are described herein. In some embodiments, a system includes
a processing sub-system configured to receive a municipal solid waste
stream and to remove the non-processable waste, a processing apparatus
configured and disposed to receive constituents of the municipal solid
waste stream from the processing sub-system and reduce the size of the
constituents of the waste stream to an average particle size of less than
about 3/4 inch, and separators configured to sort the waste stream into
constituents based on density. In some embodiments, the system includes a
first separator configured and disposed to receive the constituents of
the waste stream from the processing apparatus and to separate and remove
waste constituents of a first type having a bulk density greater than
about 15 lb/ft3, and a second separator configured and disposed to
receive the constituents of the waste stream having a bulk density less
than about 15 lb/ft3 from the first separator and to separate and
remove waste constituents of a second type having a bulk density greater
than about 4 lb/ft3.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009] FIG. 1 is a flowchart illustrating a method for producing an
engineered fuel feed stock from waste material, according to an
embodiment.

[0010]FIG. 2 is a schematic illustration of a system for producing an
engineered fuel feed stock from waste material, according to an
embodiment.

[0011]FIG. 3 is a schematic illustration of a material classification
subsystem included in the system illustrated in FIG. 2, according to an
embodiment.

[0012]FIG. 4 is a schematic illustration of a material classification
subsystem included in the system illustrated in FIG. 2, according to an
embodiment.

[0013]FIG. 5 is a schematic illustration of a material classification
subsystem included in the system illustrated in FIG. 2, according to an
embodiment.

[0014]FIG. 6 is a schematic illustration of a material classification
subsystem included in the system illustrated in FIG. 2, according to an
embodiment.

[0015] FIG. 7 is a schematic illustration of a system for producing an
engineered fuel feed stock from waste material, according to an
embodiment.

[0016]FIG. 8 is a schematic illustration of a system for producing an
engineered fuel feed stock from waste material, according to an
embodiment.

[0017] FIGS. 9A-9F are top views of a fuel feed stock in a first, second,
third, fourth, fifth, and sixth configuration, respectively, according to
an embodiment.

[0018] FIG. 10 is a top view of a fuel feed stock in a first stage and in
a first, second, third, fourth, fifth, sixth, seventh, eighth, ninth, and
tenth configuration, respectively, according to an embodiment.

[0019]FIG. 11 is a top view of the fuel feed stock illustrated in FIG. 10
in a second stage and in a first, second, third, fourth, fifth, sixth,
seventh, eighth, ninth, and tenth configuration, respectively.

DETAILED DESCRIPTION

[0020] Systems and methods for producing engineered fuels from solid waste
material are described herein. In some embodiments, a method includes
receiving a waste stream at a multi-material processing platform and
separating the waste stream to remove non-processable waste, prohibitive
items and marketable recyclables. The method further includes conveying
processable materials to a material classification system and
incorporating additives to produce an engineered fuel from the
constituents of the waste stream.

[0021] The term "about" generally means plus or minus 10% of the value
stated, e.g. about 5 would include 4.5 to 5.5, about 10 would include 9
to 11, about 100 would include 90 to 110.

[0022] The term "carbon content" means all carbon contained in the fixed
carbon (see definition below) as well as in all the volatile matters in
the feed stock.

[0023] The term "commercial waste" means solid waste generated by stores,
offices, restaurants, warehouses, and other non-manufacturing,
non-processing activities. Commercial waste does not include household,
process, industrial or special wastes.

[0024] The term "construction and demolition debris" (C&D) means
uncontaminated solid waste resulting from the construction, remodeling,
repair and demolition of utilities, structures and roads; and
uncontaminated solid waste resulting from land clearing. Such waste
includes, but is not limited to bricks, concrete and other masonry
materials, soil, rock, wood (including painted, treated and coated wood
and wood products), land clearing debris, wall coverings, plaster,
drywall, plumbing fixtures, non-asbestos insulation, roofing shingles and
other roof coverings, asphaltic pavement, glass, plastics that are not
sealed in a manner that conceals other wastes, empty buckets ten gallons
or less in size and having no more than one inch of residue remaining on
the bottom, electrical wiring and components containing no hazardous
liquids, and pipe and metals that are incidental to any of the above.
Solid waste that is not C&D debris (even if resulting from the
construction, remodeling, repair and demolition of utilities, structures
and roads and land clearing) includes, but is not limited to asbestos
waste, garbage, corrugated container board, electrical fixtures
containing hazardous liquids such as fluorescent light ballasts or
transformers, fluorescent lights, carpeting, furniture, appliances,
tires, drums, containers greater than ten gallons in size, any containers
having more than one inch of residue remaining on the bottom and fuel
tanks. Specifically excluded from the definition of construction and
demolition debris is solid waste (including what otherwise would be
construction and demolition debris) resulting from any processing
technique, that renders individual waste components unrecognizable, such
as pulverizing or shredding.

[0025] The term "fiber" means materials including, but not limited to,
textiles, wood, biomass, papers, fiberboard and cardboard. In addition,
the term "fibers" can refer to the aforementioned materials with a bulk
density of about 4 pounds per cubic foot, and generally include naturally
occurring or man-made products based on woody, cellulostic or
lignocellulostic biomass, plants and living stocks. In terms of chemical
characteristics, the fiber materials typically have a carbon content of
35-50 wt, % with an average of about 45 wt, %, a hydrogen content of 5-7%
wt. % with an average of about 6 wt. %, an oxygen content of 35-45 wt. %
with an average of about 40 wt. %, and a higher heating value of about
6,000-9,000 Btu/lb with an average of about 7,500 Btu/lb, all in a dry
basis.

[0026] The term "fixed carbon" means the balance of material after
moisture, ash, and volatile matter are excluded, as determined by
proximate analysis.

[0027] The term "garbage" means putrescible solid waste including animal
and vegetable waste resulting from the handling, storage, sale,
preparation, and cooking or serving of foods. Garbage originates
primarily in home kitchens, stores, markets, restaurants and other places
where food is stored, prepared or served.

[0028] The term "hard plastic", also referred to as rigid plastic, means
plastic materials including, but not limited to, high-density
polyethylene, polyethylene terephthalate, and polyvinyl chloride. In
addition, the term "hard plastic" can refer to the aforementioned
materials with a bulk density of about 15-25 pounds per cubic foot and
actual material density of about 56-87 pounds per cubic foot.

[0029] The term "hazardous waste" means solid waste that exhibits one of
the four characteristics of a hazardous waste (reactivity, corrosivity,
ignitability, and/or toxicity) or is specifically designated as such by
the EPA as specified in 40 CFR part 262.

[0030] The term "marketable recyclables" means materials for which there
is an active market where the materials can be sold as commodities,
including but not limited to, old corrugated cardboard (OCC), old
newspaper (ONP), mixed paper, high-density polyethylene (HDPE),
polyethylene terephthalate (PET), mixed plastics, ferrous metals, and/or
nonferrous metals, and glass.

[0031] The term "municipal solid waste" (MSW) means solid waste generated
at residences, commercial or industrial establishments, and institutions,
and includes all processable wastes along with all components of
construction and demolition debris that are processable, but excluding
hazardous waste, automobile scrap and other motor vehicle waste, used
tires, infectious waste, asbestos waste, contaminated soil and other
absorbent media and ash other than ash from household stoves. Components
of municipal solid waste include without limitation plastics, fibers,
paper, yard waste, rubber, leather, wood, and also recycling residue, a
residual component containing the non-recoverable portion of recyclable
materials remaining after municipal solid waste has been processed with a
plurality of components being sorted from the municipal solid waste.

[0032] The term "non-processable waste" (also known as noncombustible
waste) means waste that does not readily gasify in gasification systems
and does not give off any meaningful contribution of carbon or hydrogen
into the synthesis gas generated during gasification. Non-processable
wastes include but are not limited to: batteries, such as dry cell
batteries, mercury batteries and vehicle batteries; refrigerators;
stoves; freezers; washers; dryers; bedsprings; vehicle frame parts;
crankcases; transmissions; engines; lawn mowers; snow blowers; bicycles;
file cabinets; air conditioners; hot water heaters; water storage tanks;
water softeners; furnaces; oil storage tanks; metal furniture; propane
tanks; and yard waste.

[0033] The term "processed MSW waste stream" means that MSW has been
processed at, for example, a materials recovery facility, by having been
sorted according to types of MSW components. Types of MSW components
include, but are not limited to, plastics, including soft plastics and
hard plastics (e.g., #1 to #7 plastics and other polymers such as
Acrylonitrile-butadiene-styrene (ABS), Polyamide (also called nylon, PA),
Poly(butylene terephtha late)--PBT), fibers, paper, yard waste, rubber,
leather, wood, and also recycling residue, a residual component
containing the non-recoverable portion of recyclable materials remaining
after municipal solid waste has been processed with a plurality of
components being sorted from the municipal solid waste. Processed MSW
contains substantially no glass, metals, or grit. Grit includes dirt,
dust, and sand, and as such the processed MSW contains substantially no
non-combustibles.

[0034] The term "processable waste" means wastes that is readily
processable by equipment such as shredders, density separators, optical
sorters, etc. and can be used as fuel feedstock in thermal and biological
conversion processes. Processable waste includes, but is not limited to,
newspaper, junk mail, corrugated cardboard, office paper, magazines,
books, paperboard, other paper, rubber, textiles, and leather from
residential, commercial, and institutional sources only, wood, food
wastes, and other combustible portions of the MSW stream.

[0035] The term "recycling residue" means the residue remaining after a
recycling facility has processed its recyclables from incoming waste
which cannot be marketed and thus no longer contains economic value from
a recycling point of view.

[0036] The term "sludge" means any solid, semisolid, or liquid generated
from a municipal, commercial, or industrial wastewater treatment plant or
process, water supply treatment plant, air pollution control facility or
any other such waste having similar characteristics and effects.

[0037] The term "soft plastics" means plastic films, bags and foams, such
as low density polyethylene, expanded polystyrene, and extruded
polystyrene foam. In addition, the term "soft plastic" can refer to the
aforementioned materials with a bulk density of about 1-4 pounds per
cubic foot and which are typically two-dimensional or flat in shape.

[0038] The term "solid waste" means unwanted or discarded solid material
with insufficient liquid content to be free flowing, including, but not
limited to rubbish, garbage, scrap materials, junk, refuse, inert till
material, and landscape refuse, but does not include hazardous waste,
biomedical waste, septic tank sludge, or agricultural wastes, animal
manure and absorbent bedding used for soil enrichment or solid or
dissolved materials in industrial discharges. The fact that a solid
waste, or constituent of the waste, may have value, be beneficially used,
have other use, or be sold or exchanged, does not exclude it from this
definition.

[0039] The term "sorbent" means a material added to the engineered fuel
feed stock that either acts as a traditional sorbent and adsorbs a
chemical or elemental by-product, or reacts with a chemical or elemental
by-product, or in other cases, simply as an additive to alter the fuel
feed stock characteristics such as ash fusion temperature.

[0040] In some embodiments, a waste management system includes a tipping
floor, a screen, a primary shredder, a secondary shredder, a set of
separators, a material classification subsystem, and an engineered fuel
production subsystem. In some embodiments, the tipping floor can be
configured to receive at least a portion of a waste stream to be
processed within or by the waste management system. The screen is
configured to process the incoming waste by removing undersized fraction
of the waste consisting primarily of non combustibles, batteries, and
food waste. The primary shredder is configured to shred the waste
material to a predetermined size such that remaining non-processable and
non-combustible waste can be separated from the waste stream by the set
of separators. The set of separators can include a magnetic separator, an
eddy current separator, an optical separator, and/or a glass separator.
The secondary shredder can be configured to receive the processable waste
stream and shred the processable waste to a predetermined size. The
material classification subsystem can be configured to further separate
classify) the processable waste and deliver the classified waste to the
engineered filet production subsystem. The engineered fuel production
subsystem is configured to receive the classified waste material from the
material classification subsystem and selectively produce an engineered
fuel.

[0041] FIG. 1 is a flowchart illustrating a method 100 for producing an
engineered fuel feed stock from solid waste material. The method 100
includes conveying a waste stream to a multi-material processing platform
102, in some embodiments, the waste stream can be, for example, MSW,
recycling residue, and/or any combination thereof. In some embodiments,
the waste stream can be delivered to a tipping floor of a waste material
receiving facility. The method 100 includes separating non-processables
and prohibitives 104 from the waste stream. In some embodiments, the
non-processables can be removed from the waste stream before the waste
stream is conveyed to the tipping floor of the waste material receiving
facility (e.g., at a previous waste handling facility).

[0042] The method 100 further includes separating marketable recyclables
106 from the waste stream. The marketable recyclables can be separated
using any suitable method. In some embodiments, the marketable
recyclables are separated manually (e.g., by hand). In other embodiments,
the waste stream can be fed into a separator and/or series of separators.
For example, in some embodiments, the separators can include a magnetic
separator (e.g., to remove ferrous metals), a disc separator (e.g., to
remove relatively large pieces of OCC, ONP, mixed plastics, etc.), an
eddy current separator (e.g., to remove non-ferrous metals), an optical
sorter separator and/or any other suitable separator (e.g. XRF sensor
based separator). In this manner, materials with a sufficiently high
market value can be removed (e.g., separated) from the waste stream and
further processed (e.g., bailed, stored, shipped, etc.) to be sold as a
marketable material. Systems and methods of processing and sorting
marketable recyclables are described in U.S. Pat. No. 7,264,124 to Bohlig
et al., filed Nov. 17, 2004, entitled "Systems and Methods for Sorting
Recyclables at a Material Recovery Facility," U.S. Pat. No. 7,341,156 to
Bohlig et al., filed Apr. 15, 2005, entitled "Systems and Methods for
Sorting, Collecting Data Pertaining to and Certifying Recyclables at a
Material Recovery Facility," and U.S. Patent Publication No. 2008/0290006
to Duffy et al., filed May 23, 2007, entitled "Systems and Methods for
Optimizing a Single-Stream Materials Recovery Facility," the disclosures
of which are hereby incorporated herein by reference, in their
entireties.

[0043] With the non-processables, prohibitives and the marketable
recyclables removed from the waste stream, the waste stream can be
conveyed to a material classification subsystem 108. In some embodiments,
the conveying of the waste stream can include passing the waste stream
through at least one shredder configured to reduce the size of the
constituents of the waste stream. For example, in some embodiments, the
shredder can be configured to reduce the size of the constituents of the
waste stream to be less than about 4 inches. In other embodiments, the
shredder can be configured to reduce the size of the constituents of the
waste stream to be between about 0.75 inches and about 1 inch. In still
other embodiments, the shredder can be configured to reduce the size of
the constituents of the waste stream to be between about 0.1875 inches
and about 0.25 inches. With the size of the constituents of the waste
stream reduced, the conveying of the waste stream to the material
classification subsystem can further include passing the waste stream
through a set of separators. In some embodiments, the set of separators
can include, for example, a density separator, a magnetic separator, an
eddy current separator, a glass separator, and/or the like. For example,
in some embodiments, the shredded waste stream can pass through a density
separator such that materials with a density below a predetermined
threshold pass to the material classification subsystem and material with
a density above the predetermined threshold pass to a secondary subsystem
(e.g., further separated to remove marketable recyclables not separated
in the first separation process) and/or are disposed of (e.g., conveyed
to a landfill).

[0044] The material classification subsystem can be configured to further
separate a desired set of materials. For example, in some embodiments,
the material classification subsystem receives a waste stream including
hard plastics, soft plastics, and/or fibers. In such embodiments, the
material classification subsystem can separate the hard plastics, soft
plastics, and/or fibers via any suitable method. For example, in some
embodiments, the material classification subsystem can include cyclonic
separators, fluidized beds, density separators, and/or the like. With the
waste stream further separated by the material classification subsystem,
the method 100 includes selectively mixing additive material 110 to one
or more components of the separated waste stream. The additive material
can include, for example, chemical additives, sorbents, biomass waste
(e.g., wood), biomaterials (e.g., animal manure), and/or any other
suitable additive. With the additive material mixed with at least a
portion of the waste stream, the portion of the waste stream can be
processed into an engineered fuel feed stock 112.

[0045] In some embodiments, at least a portion of the waste stream and the
additive material can be compressed to form a densified intermediate
material. The densified intermediate material can be in the form of
cubes, briquettes, pellets, honeycomb, or other suitable shapes and
forms. For example, in some embodiments, chemical additives (e.g.,
sorbents, nutrients, promoters, and/or the like) can be mixed with hard
plastics and/or soft plastics that have been separated from the waste
stream by the material classification subsystem, and then compressed to
form pellets such that the additives are evenly distributed (i.e.,
substantially homogeneous) and integrated (i.e., bound) within the
plastic pellets. In some embodiments, the densified intermediate material
can be used as an engineered fuel feed stock in, for example, combustion
power plants (e.g., coal burning power plants). In other embodiments, the
densified intermediate material can be combined with a second portion of
the waste stream (e.g., the soft plastic and/or the fiber) and processed
(e.g., compressed). In still other embodiments, the densified
intermediate material can be granulated and/or pulverized to any suitable
particle size, combined with a second portion of the waste stream and/or
additional additives, and then compressed to form a densified engineered
fuel feed stock. In this manner, the constituents of the separated waste
stream (e.g., the constituents of the waste stream after material
classification) can be combined with additives (and/or portions of
previously processed materials) to produce a substantially homogeneous
engineered fuel feed stock that includes inseparable additives, as
described in further detail herein.

[0046]FIG. 2 is a schematic illustration of a system 200 for producing an
engineered fuel feed stock from solid waste material. The system 200
includes at least a tipping floor F, a primary shredder 230, a secondary
shredder 235, a density separator 243, a magnetic separator 244, an eddy
current separator 245, a glass separator 246, a material classification
subsystem 220, and a fuel feed stock production subsystem 280 (also
referred to herein as "engineered fuel subsystem 280" or "EF subsystem
280"). In some, embodiments, a waste stream is conveyed to the tipping
floor F, as shown by arrow AA. The waste stream can be, for example, MSW
delivered via a collection truck or recycling residue from a recycling
facility. In other embodiments, the solid waste can be delivered via a
conveyer from a material recovery facility or other waste handling
facility.

[0047] The waste stream, at least partially disposed on the tipping floor
F, is configured to be separated such that non-processables, prohibitives
and/or marketable recyclables (as described above) are removed (e.g.,
separated) from the waste stream. In some embodiments, the tipping floor
is configured to have manual removal of bulky items, screen separators to
remove undersized materials such as batteries, electronic parts, food
waste, and noncombustibles.

[0048] While not shown in FIG. 2, the system 200 can include any number of
conveyers and/or transport mechanisms configured to convey at least a
portion of the waste stream from a portion of the system 200 to a second
portion of the system 200. In this manner and with the non-processables,
prohibitives and the marketable recyclables removed from the waste
stream, the waste stream can be conveyed to the primary shredder 230. In
some embodiments, the primary shredder 230 can further be configured to
receive recycling residue, as shown by the arrow BB in FIG. 2. For
example, in some embodiments, the primary shredder 230 can receive the
waste stream conveyed from the tipping floor F and recycling residue
delivered from, for example, a material recovery facility.

[0049] The primary shredder 230 can be any suitable shredder configured to
reduce the size of the constituents of the waste stream to a suitable
size. For example, in some embodiments, the constituents of the waste
stream can be reduced to a size less than about 10-12 inches. In other
embodiments, the shredder can be configured to reduce the size of the
constituents of the waste stream to be less than 4 inches, and in still
other embodiments the shredder can be configured to reduce the size of
the constituents of the waste stream to be between about 0.75 inches and
about 1 inch.

[0050] The system 200 can further include a conveyer configured to
transfer a portion of the waste stream from the primary shredder 230 to
the density separator 243. The conveying of the material can be
pneumatically (via air blower) or mechanically (e.g. screw conveyor). The
density separator 243 can be configured such that a first set of
constituents of the waste stream with a density below a predetermined
density threshold (e.g., plastics and/or fibers) pass through the density
separator 243 to the secondary shredder 235. A second set of constituents
of the waste stream with a density above the predetermined density
threshold (e.g., ferrous metals, non-ferrous metals, glass, dirt, and/or
the like) are configured to pass through the density separator 243 to
additional separations processes. For example, the metals, glass, dirt,
etc. can be conveyed to the magnetic separator 244 where the marketable
ferrous metals (e.g., steel) are recovered. The remaining metals, glass,
dirt, etc, can be conveyed to the eddy current separator 245 where the
marketable non-ferrous metals (e.g., aluminum) are recovered. The
residual non-metallic material can then optionally be conveyed to the
glass separator 246 to remove the glass particles. In some embodiments,
the glass separator 246 is an optical glass separator. In other
embodiments, the glass separator 246 can be any suitable separator. With
the portion of the waste stream substantially free of metals and/or
glass, the remaining constituents (e.g., residues) can be disposed of in,
for example, a landfill, if no other beneficial use of the material can
be identified. In some embodiments where recycled glass does not have a
market value, the glass separator can be omitted and/or bypassed and the
glass can be disposed of with the residues at a landfill, or used as
daily cover material in landfill.

[0051] As described above, the first set of constituents of the waste
stream (e.g., the plastics and fibers with a density below the density
threshold of the density separator 243) are conveyed to the secondary
shredder 235. The secondary shredder 235 can be any suitable shredder.
For example, in some embodiments, the secondary shredder 235 is
substantially similar to the primary shredder 230. In other embodiments,
the secondary shredder 235 is different from the primary shredder 235.
Furthermore, the secondary shredder 235 can be configured to shred the
constituents of the waste stream to any suitable size, e.g. a smaller
size than produced by the primary shredder 235. For example, in some
embodiments, the secondary shredder is configured to shred the
constituents to a size between about 0.375 (3/8'') inches and about 0.25
(1/4'') inches. In other embodiments, the secondary shredder 235 can
shred the constituents of the waste stream to a size less than or equal
to about 0.09375 ( 3/32'') inches.

[0052] In some embodiments, the density separator 243 can be configured to
include multiple stages and/or portions. For example, in some
embodiments, the waste stream can be delivered to a screen included in
the density separator 243. In such embodiments, the screen can define a
predetermined mesh size and can be configured to separate the waste
stream into a first portion including a constituent size of less than the
mesh size and a second portion including a constituent size greater than
mesh size. In some embodiments, the first portion of the waste stream can
be delivered to a first density separator (not shown) and the second
portion of the waste stream can be delivered to a second density
separator (not shown). In some embodiments, for example, the screen can
define a mesh size of about 0.25 inches. In some embodiments, the
separation of the waste stream into the first portion, having the first
constituent size, and the second portion, having the second constituent
size, can increase the efficiency of the first density separator and/or
the second separator. In such embodiments, constituents of greater size
can, for example, reduce the efficiency of the first separator, cause the
first separator to malfunction, and/or cause the first separator
inadequately separate the constituents. With the constituents separated
by the first density separator or the second density separator, the
constituents with a density greater than the density threshold (e.g.,
ferrous metals, non-ferrous metals, glass, dirt, and/or the like) are
conveyed to the set of separators, as described above. Furthermore, the
constituents of the waste stream with a density below the density
threshold of the first density separator and/or the second density
separator (e.g., the plastics and fibers) can be conveyed to the
secondary shredder 235.

[0053] In some embodiments, the waste stream can be conveyed from the
secondary shredder 235 to an additional density separator configured to
separate the constituents of the waste stream, as described above. In
such embodiments, the additional density separator can be used to ensure
the waste stream is substantially free from metals, glass, and/or any
other material that can, for example, have adverse effects on the
material classification subsystem 220. With the size of the constituents
of the waste stream reduced to a predetermined size and the waste stream
sufficiently separated, the waste stream can be transferred to the
material classification subsystem 220.

[0054] The material classification subsystem 220 can be any suitable
system configured to further separate (e.g., classify) a desired set of
material. For example, in some embodiments, the material classification
subsystem 220 receives the portion of the waste stream having a density
below the density threshold of the density separator 243 (e.g., plastics
and fibers). In such embodiments, the material classification subsystem
220 can separate the incoming material into, for example, hard plastic,
soft plastic, and/or fiber via any suitable method. In some embodiments,
the material classification subsystem 220 can include cyclonic
separators, fluidized beds, density separators, and/or the like. In this
manner, the material classification subsystem 220 can separate the waste
stream and store the separated constituents in, for example, bunkers (not
shown in FIG. 2).

[0055] The system 200 can further include a delivery mechanism (e.g., a
conveyer) to convey the hard plastic, the soft plastic, and/or the fiber
to the fuel feed stock production subsystem 280. The EF subsystem 280 can
be any suitable system. For example, in some embodiments, the EF
subsystem 280 can include a portion configured to deliver additives to
the waste stream (e.g., chemical additives, sorbents, biomass,
biomaterials, and/or the like), a milling portion, an extrusion portion,
and/or any other suitable portion.

[0056] Expanding further, in some embodiments, the portion of the waste
stream (e.g., the hard plastic, soil plastic, and/or fiber) can be mixed
with the additives and compressed to form, for example, a densified
intermediate material, as described above. In this manner, the
constituents of the separated waste stream (e.g., the constituents of the
waste stream conveyed from the material classification subsystem 220) can
be combined with additives and/or portions of processed materials and
processed to produce an engineered fuel feed stock, as described in
further detail herein.

[0057] While the primary shredder 230 described with respect to FIG. 2 is
shown receiving both municipal solid waste and recycling residue, in some
embodiments, a primary shredder can be configured to receive only
recycling residue. For example, as shown in FIG. 3, a system 300 includes
at least a primary shredder 330, a material classification subsystem 320,
and a set of conveyers C. The (primary shredder 330 can be any suitable
shredder or shredders. For example, in some embodiments, the primary
shredder 330 can be substantially similar to the primary shredder 230
described above with respect to FIG. 2. In some embodiments, the material
classification subsystem 320 can further include a secondary shredder
335, a set of cyclonic separators 341, a set of bunkers 360, a dust
filter 352, and a blower 370. The set of cyclonic separators 341 can be
any suitable cyclonic separators. For example, the cyclonic separators
341 can be configured such that a gas (e.g., air) flows within the
cyclonic separator 341 in a helical manner. The cyclonic separators 341
can further be configured such that the flow rate of the air, within the
cyclonic separators, separates materials based on a predetermined density
threshold, as described in further detail herein.

[0058] The primary shredder 330 can be configured to receive recycling
residue, as shown by the arrow CC in FIG. 3. With the system 300
receiving recycling residue, the use of multiple separation devices for
removing undesired materials from the waste stream (e.g., a magnetic
separator, an eddy current separator, and/or a glass separator) can be
reduced to using the material classification subsystem 320, as shown in
FIG. 3. Similarly stated, since the waste stream is substantially limited
to recycling residue, the need for certain separators (e.g., the magnetic
separator, the eddy current separator, and/or the glass separator) is
reduced or eliminated because the waste stream includes a limited amount
of constituents separated by those separators. Said yet another way, the
waste stream of the system 300 is sufficiently free from non-processables
(e.g., metals, glass, dirt, and/or the like) that the material
classification subsystem 320 can be employed to substantially remove the
undesirable material and/or classify the waste stream.

[0059] In this manner, a first conveyer C can be configured to convey the
shredded material (e.g., the waste stream shredded to a size of about
0.375 inches) to the material classification subsystem 320. More
specifically, the first conveyer C can be configured to convey the
shredded material to a first cyclonic separator 341A to remove, for
example, glass, metal, and/or dirt fines. Expanding further, the first
cyclonic separator 341A can define a flow rate such that a portion of the
waste stream (e.g., glass, metals, and/or dirt fines) is sufficiently
dense to fall through the first cyclonic separator 341A and into a first
bunker 360A. Conversely, a second portion of the waste stream (e.g.,
plastics and/or fibers) has a sufficiently lower density such that it is
entrained in the air flow of the first cyclonic separator 341A. In this
manner, the second portion of the waste stream is transferred from the
first cyclonic separator 341A to the secondary shredder 335.

[0060] The secondary shredder 335 can be configured to shred the
constituents of the waste stream to any suitable size, as described
above. With the size of the constituents of the waste stream reduced, the
waste stream can be delivered via a second conveyer C to a second
cyclonic separator 341B. The second cyclonic separator 3419 can be
substantially similar in form and function to the first cyclonic
separator 341A. However, in some embodiments, the flow rate of the second
cyclonic separator 3419 can be such that the second cyclonic separator
3419 is configured to separate hard plastic material from the waste
stream. Similarly stated, in some embodiments, hard plastics in the waste
stream have a density that is sufficiently higher than the other
components of the waste stream so that the hard plastics fall to the
bottom of the second cyclonic separator 341B and are stored in a second
bunker 360B. Furthermore, the portion of the waste stream (e.g., soft
plastics and/or fibers) having a lower density remains entrained in the
air flow of the second cyclonic separator 341B and is transferred from
the second cyclonic separator 341B to a third cyclonic separator 341C.

[0061] The third cyclonic separator 341C can be substantially similar in
form and function to the first cyclonic separator 341A and/or the second
cyclonic separator 3419. However, in some embodiments, the flow rate of
the third cyclonic separator 341C can be such that the third cyclonic
separator 341C is configured to separate fibers (e.g., papers and/or the
like) from the waste stream. Similarly stated, in some embodiments,
fibers in the waste stream have a density that is sufficiently higher
than the other components of the waste stream so that the fibers fall to
the bottom of the third cyclonic separator 341C and are stored in a third
bunker 360C. Furthermore, the portion of the waste stream (e.g., soft
plastics) having a lower density remains entrained in the air flow of the
third cyclonic separator 341C and is transferred from the third cyclonic
separator 341C to a fourth cyclonic separator 341D.

[0062] The fourth cyclonic separator 341D can be substantially similar in
form and function to the cyclonic separators 341A, 3419, and/or 341C.
However, in some embodiments, the flow rate of the fourth cyclonic
separator 341D can be such that soft plastics are separated from the
waste stream. Similarly stated, in sonic embodiments, soft plastics in
the waste stream have a density that is sufficiently higher than the
other components of the waste stream so that the soft plastics fall to
the bottom of the fourth cyclonic separator 341D and are stored in a
fourth bunker 360D. Furthermore, the portion of the waste stream (e.g.,
dust particles) having a lower density remains entrained in the air flow
of the fourth cyclonic separator 341D and is transferred from the fourth
cyclonic separator 3411) to the dust filter 352, configured to
substantially remove dust particles from the air. With the air
substantially free of dust, the air can be delivered to the blower 370.
In some embodiments, the blower 370 is configured to feed a portion of
the air to the first, second, third, and/or fourth cyclonic separator
341A, 341B, 341C, 341D, respectively. In other embodiments, the blower
370 can be configured to vent the air, for example, to the atmosphere.

[0063] While the material classification subsystem 320 is described as
including cyclonic separators 341, in sonic embodiments, a material
classification subsystem can include any suitable separator and/or
combination of separators. For example, as shown in FIG. 4, a material
classification subsystem 420 includes a cyclonic separator 441 and a
fluidized bed separator 447. Expanding further, the material
classification subsystem 420 includes a granulator 432 configured to
receive a waste stream, as shown by the arrow DD. In some embodiments,
the waste stream can be recycling residue. In other embodiments, the
waste stream can be a portion of a municipal solid waste stream (e.g.,
MSW substantially free from metals, glass, and/or any other
non-processables or marketable recyclables).

[0064] The granulator 432 can be configured to reduce the size of the
constituents of the waste stream, in some embodiments, the granulator 432
is configured to shred the constituents of the waste stream to a size
between about 0.375 inches and about 0.25 inches. In other embodiments,
the granulator 432 can shred the constituents of the waste stream to a
size less than or equal to about 0.09375 inches. With the size of the
constituents of the waste stream reduced, the shredded waste stream can
be delivered to the cyclonic separator 441. More specifically, the
material classification subsystem 420 can include a blower 470 configured
to transport the shredded waste stream from the granulator 432 to the
cyclonic separator 441. In some embodiments, the waste stream can be
conveyed through a tube, shaft, a channel, a pipe, a duct, or the like.

[0065] In some embodiments, the cyclonic separator 441 can be
substantially similar in form and function as the cyclonic separators 341
described above with respect to FIG. 3. In some embodiments, the cyclonic
separator 441 can define a flow rate such that a portion of the waste
stream (e.g., dirt, hard plastic, fiber, and soft plastic) is
sufficiently dense to pass through the cyclonic separator 441 to a
conveyer C. Said another way, the flow rate of the cyclonic separator 441
can be such that fine particles (e.g., dust and/or powders) of the waste
stream have a sufficiently low density to remain entrained in the air
flow of the cyclonic separator 441. In other embodiments, the cyclonic
separator 441 can be configured to remove or separate any suitable
constituent from the waste stream.

[0066] As described above, portions of the waste stream can pass through
the cyclonic separator 441 to the conveyer C. The portions of the waste
stream include, for example, dirt, hard plastic, fiber, and soft plastic.
The conveyer C receives the portion of the waste stream and is configured
to deliver the portion of the waste stream to the fluidized bed 447, as
shown in FIG. 4. The fluidized bed 447 includes a first chamber 448, a
second chamber, 449, a third chamber 450, and a fourth chamber 451. In
some embodiments, the fluidized bed 447 can be configured to separate
portions of the waste stream via a separation fluid (e.g., air).
Expanding further, the fluidized bed 447 can include a predetermined flow
rate and/or flow volume to separate the constituents of the waste stream
based on density. Similarly stated, with the constituents of the waste
stream reduced (e.g., by the granulator 432) to a substantially uniform
size, the separation of the waste stream into a first portion entrained
in the air flow of the fluidized bed 447 and a second portion not
entrained in the air flow of the fluidized bed 447 can be based on the
density of the constituents. In some embodiments, the feed rate of the
constituents into the fluidized bed 447 and/or the flow rate of the air
can be controlled within a predetermined range such that the fluidized
bed 447 can separate the constituents at or about a predetermined
density. Thus, the first portion of the waste stream (i.e., the portion
entrained in the air flow of the fluidized bed 447) has a density less
than the predetermined density and will float to the top of the fluidized
bed 447. The second portion (i.e., the portion not entrained in the air
flow of the fluidized bed 447) has a density greater than predetermined
density and will sink to the bottom of the fluidized bed 447. In this
manner, the first chamber 448, the second chamber 449, the third chamber
450, and the fourth chamber 451 of the fluidized bed 447 can be
configured to separate the constituents of the waste stream at or about a
first predetermined density, a second predetermined density, a third
predetermined density, and a fourth predetermined density, respectively.

[0067] As shown in FIG. 4, the first chamber 448 of the fluidized bed 447
can be configured to separate dirt from the waste stream. In such
embodiments, the first chamber 448 can be configured to separate the
constituents of the waste stream at a predetermined separation density
range between, for example, between about 25-75 pounds per cubic foot.
Therefore, the dirt in the waste stream (e.g., with density between about
75-120 pounds per cubic foot) is sufficiently dense to sink relative to
the other constituents of the waste stream and fall to the bottom of the
first chamber 448. Furthermore, a first storage bunker 460A can be
coupled to the first chamber 448 of the fluidized bed 447 such that the
as dirt sinks to the bottom of the first chamber 448, the dirt is stored
in the first bunker 460A.

[0068] As described above, a portion of the waste stream (e.g., hard
plastic, fiber, and/or soft plastic) with a density below the
predetermined separation density range of the first chamber 448 of the
fluidized bed 447 is configured to float relative to other portions
within the first chamber 448. Thus, the arrangement of the fluidized bed
447 can be such that the constituents are transferred to the second
chamber 449 of the fluidized bed 447, as shown by the arrow EE in FIG. 4.
The second chamber 449 can be configured to separate the constituents of
the waste stream at a predetermined separation density range between, for
example, the density of the hard plastics and the density of the fibers
(e.g., 6-18 pounds per cubic foot). In this manner, the hard plastics in
the waste stream (e.g., with density of about 20 pounds per cubic foot)
are sufficiently dense to sink relative to the other constituents of the
waste stream and full to the bottom of the second chamber 449.
Furthermore, a second storage bunker 460B can be coupled to the second
chamber 449 of the fluidized bed 447 such that as the hard plastic sinks
to the bottom of the second chamber 449, the hard plastic is stored in
the second bunker 460B.

[0069] A portion of the waste stream (e.g., fiber and/or soft plastic)
with a density below the predetermined separation density range of the
second chamber 449 of the fluidized bed 447 is configured to float
relative to the other portions within the second chamber 449. Thus, the
arrangement of the fluidized bed 447 can be such that the constituents
are transferred to the third chamber 450 of the fluidized bed 447, as
shown by the arrow FF in FIG. 4. The third chamber 450 can be configured
to separate the constituents of the waste stream at a predetermined
separation density range between, for example, the density of the fibers
and the density of the soft plastics (e.g., about 3 pounds per cubic
foot). In this manner, the fibers in the waste stream (e.g., with density
of about 4 pounds per cubic foot) are sufficiently dense to sink relative
to the other constituents of the waste stream and fall to the bottom of
the third chamber 450. Furthermore, a third storage bunker 460C can be
coupled to the third chamber 450 of the fluidized bed 447 such that as
the fiber sinks to the bottom of the third chamber 450, the fiber is
stored in the third bunker 460C.

[0070] A portion of the waste stream (e.g., soft plastic) with a density
below the predetermined separation density range of the third chamber 450
of the fluidized bed 447 is configured to float relative to the other
portions within the third chamber 450. Thus, the arrangement of the
fluidized bed 447 can be such that the constituents are transferred to
the fourth chamber 451 of the fluidized bed 447, as shown by the arrow GG
in FIG. 4. The fourth chamber 451 can be configured to separate the
constituents of the waste stream at a predetermined separation density
range below, for example, the density of the soft plastics e.g., less
than 2 pounds per cubic foot). In this manner, the soft plastics in the
waste stream (e.g., with density of about 2 pounds per cubic foot) are
sufficiently dense to sink relative to the other constituents of the
waste stream and fall to the bottom of the fourth chamber 451.
Furthermore, a fourth storage bunker 460D can be coupled to the fourth
chamber 451 of the fluidized bed 447 such that as the soft plastic sinks
to the bottom of the fourth chamber 451, the soft plastic is stored in
the fourth bunker 460D. The fluidized bed 447 can be further configured
to vent excess air to stabilize the pressure within the fluidized bed
447. In some embodiments, the air can be circulated back to the blowers
470. In other embodiments, the air is vented to the atmosphere.

[0071] In some embodiments, the dirt stored in the first bunker 460A is
conveyed to a disposal system. The disposal system can be, for example,
transporting the dirt to a landfill. In other embodiments, the dirt can
be processed (e.g., cleaned) and sold. In some embodiments, the hard
plastic stored in the second bunker 460B, the fiber stored in the third
bunker 460C, and the soft plastic stored in the fourth bunker 460D are
delivered to a fuel feed stock production system, such as, for example,
those described herein. Engineered fuel feed stocks are described in U.S.
Pat. Nos. 8,157,874 and 8,157,875 to Bohlig et al., filed Apr. 14, 2011,
entitled "Engineered Fuel Feed Stock," the disclosures of which are
hereby incorporated herein by reference, in their entireties.

[0072] Referring now to FIG. 5, in some embodiments, a material
classification subsystem 520 includes a first, second, third, and fourth
cyclonic separator (541A, 541B, 541C, and 541D, respectively) and a
first, second, and third, fluidized bed separator (547A, 547B, 547C,
respectively). The material classification subsystem 520 further includes
a granulator 532 configured to receive a waste stream, as shown by the
arrow HH. In some embodiments, the waste stream can be recycling residue.
In other embodiments, the waste stream can be a portion of a municipal
solid waste stream e.g., MSW substantially free from metals, glass,
and/or any other undesired material).

[0073] The granulator 532 can be configured to reduce the size of the
constituents of the waste stream, as described above with respect to FIG.
4. With the size of the constituents of the waste stream reduced, the
shredded waste stream can be delivered to the first cyclonic separator
541A. More specifically, the material classification subsystem 520 can
include a blower 570 configured to transport the shredded waste stream
from the granulator 532 to the first cyclonic separator 541A. In some
embodiments, the waste stream can be conveyed through a tube, shaft, a
channel, a pipe, or the like.

[0074] In some embodiments, the first cyclonic separator 541A can be
substantially similar in form and function as the cyclonic separators 441
described above with respect to FIG. 4. In some embodiments, the first
cyclonic separator 541A can define a flow rate such that a portion of the
waste stream (e.g., dirt, hard plastic, fiber, and soft plastic) is
sufficiently dense to fall through the first cyclonic separator 541A to a
conveyer C. Said another way, the flow rate of the first cyclonic
separator 541A can be such that fine particles (e.g., dust and/or
powders) of the waste stream have a sufficiently low density to remain
entrained in the air flow of the first cyclonic separator 541A. In other
embodiments, the first cyclonic separator 541A can be configured to
remove or separate any suitable constituent from the waste stream.

[0075] As described above with respect to FIG. 4, portions of the waste
stream pass through the first cyclonic separator 541A to the conveyer C.
In some embodiments, the portion of the waste stream can include dirt
with a density between about 75-120 pounds per cubic foot, hard plastics
with a density of about 20 pounds per cubic foot, fibers with a density
of about 4 pounds per cubic foot, and soft plastics with a density of
about 2 pounds per cubic foot. The conveyer C receives the portion of the
waste stream and is configured to deliver the portion of the waste stream
to the first fluidized bed 547A, as shown in FIG. 5. The fluidized beds
547, as described herein, can be substantially similar in function to the
fluidized bed 447 described with respect to FIG. 4. Therefore, functional
details of the fluidized beds 547 are not described in further detail.

[0076] The first fluidized bed 547A can be configured to separate the soft
plastics (and constituents with densities less than that of soft plastics
such as, for example, dust or powders) from the waste stream. In such
embodiments, the first fluidized bed 547A can be configured to separate
the constituents of the waste stream at a predetermined separation
density range between, for example, the density of the fibers and the
density of the soft plastics (e.g., about 3 pounds per cubic foot). In
this manner, the soft plastics (e.g., with density of about 2 pounds per
cubic foot) are not sufficiently dense to sink relative to the first
fluidized bed 547A. Thus, the soft plastics (and any other constituent
with a density less the density of soft plastics) float or entrain
relative to the other constituents within the first fluidized bed 547A
and are transported to a second cyclonic separator 541B. The second
cyclonic separator 541B can include a flow rate defining a density
threshold configured to separate the soft plastic from the other
constituents. Similarly stated, the soft plastic is sufficiently dense to
fall to the bottom of the second cyclonic separator 541B and into a first
storage bunker 560A. Furthermore, constituents with a density less than
the density threshold are entrained in the air flow and can be suitably
disposed of.

[0077] Referring back to the first fluidized bed 547A, the constituents
with densities greater than the predetermined density range of the first
fluidized bed 547A sink to the bottom of the first fluidized bed 547A and
are delivered to a conveyer C. The conveyer C is configured to deliver
the constituents of the waste stream to the second fluidized bed 547B.
The second fluidized bed 547B can be configured to separate the
constituents of the waste stream at a predetermined separation density
range between, for example, about 25-70 pounds per cubic foot. Therefore,
the dirt (e.g., with density between about 75-120 pounds per cubic foot)
is sufficiently dense to sink relative to the other constituents of the
waste stream and fall to the bottom of the second fluidized bed 547B.
Furthermore, a second storage bunker 560B can be coupled to the second
fluidized bed 547B such that as the dirt sinks to the bottom of the
second fluidized bed 547B, the dirt is stored in the second bunker 560B.

[0078] A portion of the waste stream with a density below the
predetermined density range of the second fluidized bed 547B is
configured to float relative to the other portions of the second
fluidized bed 547B. Thus, the arrangement of the second fluidized bed
547B can be such that the constituents are transferred to the third
cyclonic separator 541C. The third cyclonic separator 541C can include a
flow rate defining a density threshold configured to separate the hard
plastics and the fiber from the other constituents. Similarly stated, the
hard plastics and the fibers are sufficiently dense to fall to the bottom
of the third cyclonic separator and are delivered to a conveyer C.

[0079] The third fluidized bed 547C can be configured to separate the
constituents of the waste stream at a predetermined separation density
range between, for example, the density of the hard plastics and the
density of the fibers (e.g., about 6-18 pounds per cubic foot. In this
manner, the hard plastics (e.g., with density of about 20 pounds per
cubic foot) are sufficiently dense to sink relative to the other
constituents of the waste stream and fall to the bottom of the third
fluidized bed 547C. Furthermore, a third storage bunker 5600 can be
coupled to the third fluidized bed 547C such that as the hard plastics
sink to the bottom of the third fluidized bed 547C, the hard plastics are
stored in the third bunker 560C.

[0080] A portion of the waste stream with a density below the
predetermined density range of the third fluidized bed 547C is configured
to float relative to the other portions of the third fluidized bed 547C.
Thus, the arrangement of the third fluidized bed 547C can be such that
the constituents are transferred to the fourth cyclonic separator 541D.
The fourth cyclonic separator 541D can include a flow rate defining a
density threshold configured to separate the fibers (e.g., with density
of about 4 pounds per cubic foot) from the other constituents. Similarly
stated, the fibers are sufficiently dense to fall to the bottom of the
fourth cyclonic separator and into a fourth storage hunker 560D.
Furthermore, constituents with a density less than the density threshold
are entrained in the air flow and can be suitably disposed of.

[0081] In some embodiments, the dirt stored in the second bunker 560B is
transferred to a disposal system. The disposal system can be, for
example, transporting the dirt to a landfill. In other embodiments, the
dirt can be processed (e.g., cleaned) and sold. In some embodiments, the
soft plastics stored in the first bunker 560A, the hard plastics stored
in the third bunker 560C, and the fibers stored in the fourth bunker 560D
are delivered to a fuel feed stock production system, such as, for
example, those described herein. In some embodiments, the passage of the
waste stream through cyclonic separators 541 before entering the
fluidized beds 547 can result in cleaner constituents stored in the
bunkers 560.

[0082] Referring now to FIG. 6, in some embodiments, a material
classification subsystem 620 includes a first and second cyclonic
separator (641A, 641B, respectively) and a first and second fluidized bed
separator (647A, 647B, respectively). The material classification
subsystem 620 further includes a granulator 632 configured to receive a
waste stream, as shown by the arrow II. In some embodiments, the waste
stream can be recycling residue. In other embodiments, the waste stream
can be a portion of a municipal solid waste stream (e.g., MSW
substantially free from metals, glass, and/or any other undesired
material).

[0083] The granulator 632 can be configured to reduce the size of the
constituents of the waste stream, as described above with respect to
FIGS. 4 and 5. With the size of the constituents of the waste stream
reduced, the shredded waste stream can be delivered to the first cyclonic
separator 641A. More specifically, the material classification subsystem
620 can include a blower 670 configured to transport the shredded waste
stream from the granulator 632 to the first cyclonic separator 641A. In
some embodiments, the waste stream can be conveyed through a tube, shaft,
a channel, a pipe, or the like.

[0084] In some embodiments, the first cyclonic separator 641A can be
substantially similar in form and function as the first cyclonic
separator 541A described above with respect to FIG. 5. In some
embodiments, the first cyclonic separator 641A can define a flow rate
such that a portion of the waste stream (e.g., dirt, hard plastic, fiber,
and soft plastic) is sufficiently dense to pass through the first
cyclonic separator (e.g., fall to the bottom of the first cyclonic
separator 641A) to a conveyer C. Said another way, the flow rate of the
first cyclonic separator 641A can be such that fine particles (e.g., dust
and/or powders) of the waste stream have a sufficiently low density to
remain entrained in the air flow of the first cyclonic separator 641A. In
other embodiments, the first cyclonic separator 641A can be configured to
remove or separate any suitable constituent from the waste stream.

[0085] The portions of the waste stream that pass through the first
cyclonic separator 641A can be delivered to the conveyer C. In some
embodiments, the portion of the waste stream can include dirt with a
density between about 75-120 pounds per cubic foot, hard plastics with a
density of about 20 pounds per cubic foot, fibers with a density of about
4 pounds per cubic foot, and soft plastics with a density of about 2
pounds per cubic foot. The conveyer C receives the portion of the waste
stream and is configured to deliver the portion of the waste stream to
the first fluidized bed 647A, as shown in FIG. 6. The fluidized beds 647,
as described herein, can be substantially similar in function to the
fluidized bed 447 described with respect to FIG. 4. Therefore, functional
details of the fluidized beds 647 are not described in further detail.

[0086] The first fluidized bed 647A can be configured to separate the soft
plastics (and constituents with densities less than that of soft plastics
such as, for example, dust or powders) from the waste stream. In such
embodiments, the first fluidized bed 647A can be configured to separate
the constituents of the waste stream at a predetermined separation
density range between, for example, the density of the fibers and the
density of the soft plastics (e.g., about 3 pounds per cubic foot). In
this manner, the soft plastics (e.g., with density of about 2 pounds per
cubic foot) are not sufficiently dense to sink relative to the first
fluidized bed 647A. Thus, the soft plastics (and any other constituent
with a density less the density of soft plastics) float relative to the
other constituents within the first fluidized bed 647A and are
transported to a second cyclonic separator 641B. The second cyclonic
separator 641B can include a flow rate defining a density threshold
configured to separate the soft plastic from the other constituents.
Similarly stated, the soft plastic is sufficiently dense to fall to the
bottom of the second cyclonic separator 641B and into a first storage
bunker 660A. Furthermore, constituents with a density less than the
density threshold are entrained in the air flow and can be suitably
disposed of.

[0087] Referring back to the first fluidized bed 647A, the constituents
with densities greater than the predetermined separation density of the
first fluidized bed 647A sink, to the bottom of the first fluidized bed
647A and are delivered to a conveyer C. The conveyer C is configured to
deliver the constituents of the waste stream to the second fluidized bed
647B. As shown in FIG. 6, the second fluidized bed 647B include a first
chamber 648, a second chamber 649, and a third chamber 650. The first
chamber 648 can be configured to separate the constituents of the waste
stream at a predetermined separation density range between, for example,
about 25-70 pounds per cubic foot. Therefore, the dirt (e.g., with
density between about 75-120 pounds per cubic foot) is sufficiently dense
to sink relative to the other constituents of the waste stream and fall
to the bottom of the first chamber 648. Furthermore, a second storage
bunker 660B can be coupled to the first chamber 648 of the fluidized bed
647 such that as the dirt sinks through the first chamber 648, the dirt
is stored in the second hunker 660B.

[0088] A portion of the waste stream with a density below the
predetermined density range of the first chamber 648 of the fluidized bed
647 is configured float relative to the other portions of the waste
stream within the first chamber 648. Thus, the arrangement of the
fluidized bed 647 can be such that the constituents are transferred to
the second chamber 649 of the fluidized bed 647, as shown by the arrow JJ
in FIG. 6. The second chamber 649 can be configured to separate the
constituents of the waste stream at a predetermined separation density
range between, for example, the density of the hard plastics and the
density of the fibers (e.g., about 6-18 pounds per cubic foot). In this
manner, the hard plastic (e.g., with density of about 20 pounds per cubic
foot) is sufficiently dense to sink relative to the other constituents of
the waste stream and fall to the bottom of the second chamber 649 of the
fluidized bed 647. Furthermore, a third storage bunker 660C can be
coupled to the second chamber 649 such that as the hard plastic sinks
through the second chamber 649, the hard plastics are stored in the third
bunker 660C.

[0089] A portion of the waste stream with a density below the
predetermined density range of the second chamber 649 of the fluidized
bed 647 is configured to float relative to the other portions of the
waste stream within the second chamber 648. Thus, the arrangement of the
fluidized bed 647 can be such that the constituents are transferred to
the third chamber 650 of the fluidized bed 647, as shown by the arrow KK.
The third chamber 650 can be configured to separate the constituents of
the waste stream at a predetermined separation density range between, for
example, the density of the fibers and the density of the soft plastics
(e.g., about 3 pounds per cubic foot). In this manner, the fibers (e.g.,
with density of about 4 pounds per cubic foot) are sufficiently dense to
sink relative to the other constituents of the waste stream and fall to
the bottom of the third chamber 650 of the fluidized bed 647.
Furthermore, a fourth storage bunker 660D can be coupled to the third
chamber 650 of the fluidized bed 647 such that as the fibers sink through
the third chamber 650, the fibers are stored in the fourth bunker 660D.

[0090] FIG. 7 is a schematic illustration of a system 700 for producing an
engineered fuel feed stock from solid waste material. The system 700
includes at least a separation subsystem 715 and a fuel feed stock
production subsystem 780 (also referred to herein as "engineered fuel
subsystem 780" or "EF subsystem 780" or "Advanced Product Manufacturing
(APM) subsystem 780"). In some embodiments, a waste stream can be
transferred to the separation subsystem 715, as shown by arrow LL in FIG.
7. The waste stream can be, for example, MSW delivered via a collection
truck or recycling residue from a recycling facility. In other
embodiments, the solid waste can be delivered via a conveyer from a
material recovery facility or other waste handling facility. The
separation subsystem 715 can be configured to separate the waste stream
that non-processables and/or marketable recyclables are removed (e.g.,
separated) from the waste stream. Expanding further, the separation
subsystem 715 can be any of the systems described with reference to FIGS.
2-6 or any combination thereof. In some embodiments, the separation
subsystem 715 can include any number of separators (e.g., magnetic
separators, eddy current separators, glass separators, fluidized bed
separators, cyclonic separators, and/or the like), shredders and
granulators. In this manner, the separation subsystem 715 can receive a
waste stream (e.g., MSW and/or recycling residue) and transfer separated
constituents of the waste stream into bunkers 760. For example, in some
embodiments, the material classification subsystem 720 can include a
first bunker configured to store hard plastics, a second bunker
configured to store soft plastics, and a third bunker configured to store
fibers. In this manner, the system 700 can further include a delivery
mechanism (e.g., a conveyers, tubes, pipes, channels, and/or the like) to
convey the hard plastics, the soft plastics, and/or the fibers to the EF
subsystem 780.

[0091] The EF subsystem 780 can be any suitable system suitable for
combining the classified waste materials with additives in predetermined
ratios to produce an engineered fuel feed stock. The EF subsystem 780 can
include, for example, a portion configured to deliver additives to the
waste stream (e.g., chemical additives, sorbents, biomass, biomaterials,
and/or the like), conditioners, mixers, conveyers, densifiers,
granulators, pulverizers, storage bunkers, and/or any other suitable
devices or systems.

[0092] In some embodiments, at least a portion of the waste stream can be
delivered to the EF subsystem 780 to produce an engineered fuel feed
stock. Expanding further, in some embodiments, the material
classification subsystem 715 can be configured to deliver a given
quantity of the hard plastics to the EF subsystem 780. In such
embodiments, the hard plastics can be passed through a pre-treatment
mechanism 756. The pre-treatment mechanism 756 can be, for example, a
heater configured to raise the temperature of the hard plastics. In some
embodiments, the pretreatment mechanism can receive at least a portion of
the sorbent 790. In still other embodiments, the soft plastic portion
delivered to the mixer 754A can be first directed to the pretreatment
mechanism 756. The EF subsystem 780 can further include a set of mixers
754 configured to receive at least a portion of the waste stream
delivered by the material classification subsystem 720 and metering
devices 775 configured to control the flow of the waste stream into the
mixers 754.

[0093] The mixers 754 can be any suitable device such as paddled
continuous mixer, rotary continuous mixer, screw conveyor or auger
conveyor mixer, mechanically vibrating or agitating mixer. In some
embodiments, the material classification subsystem 715 can deliver a
first waste stream including hard plastics and a second waste stream
including soft plastics to a first mixer 754A. In such embodiments, the
first mixer 754A is configured to mix a metered amount of the hard
plastics with a metered amount of the soft plastics. In this manner, the
first mixer 754A can deliver the mixed waste stream to a blower 770
configured to feed the waste stream to a first conditioner 755A. In other
embodiments, the hard plastics can be configured to pass through the
first mixer 754A and remain substantially unmixed (e.g., the metering
mechanism 775 does not supply a quantity of the soft plastics). In this
manner, a waste stream including substantially only hard plastics can be
delivered to the first conditioner 755A, as further described herein.

[0094] The first conditioner 755A can be any suitable device and/or system
configured to condition at least a portion of the waste stream for
engineered fuel feed stock production. For example, in some embodiments,
the first conditioner 755A can be configured to increase the temperature
of the constituents of the waste stream (e.g., the hard plastics). In
some embodiments, the first conditioner 755A can be configured to
increase the moisture of the constituents of the waste stream. In some
embodiments, the first conditioner 755A can receive the portion of the
waste stream and a set of additives. In some embodiments, the additives
can be chemical additives (e.g., sorbents, nutrients, promoters, and/or
the like), biomass waste (e.g., wood), biomaterials (e.g., animal
manure), and/or any other suitable additive or additives, in solids or
solution form (e.g. urea, acetic acid, mercury oxidizing agents such as
calcium bromide, ammonium bromide, sodium bromide, etc., for mercury
reduction). For example, in some embodiments, the first conditioner 755A
can be configured to receive a sorbent 790. In such embodiments, the
sorbent 790 can be configured to alter the combustion properties of the
constituents of the waste stream. For example, in some embodiments, the
sorbent 790 can be configured to absorb sulfur dioxide (SO2). In
other embodiments, the sorbent 790 can be configured to absorb and/or
neutralize odors, burn with a given color, and/or the like. In some
embodiments, the sorbent 790 can be conditioned by a second conditioner
755B prior to being delivered to the first conditioner 755A, in such
embodiments, the second conditioner 755B can be configured to, for
example, raise the temperature of the sorbent 790. Examples of additives
that can be incorporated into the engineered fuel feed stock using the
subsystem 780 include sodium sesquicarbonate (Trona), sodium bicarbonate,
sodium carbonate, zinc ferrite, zinc copper ferrite, zinc titanate,
copper ferrite aluminate, copper aluminate, copper managanese oxide,
nickel supported on alumina, zinc oxide, iron oxide, copper, copper (I)
oxide, copper (II) oxide, limestone, lime, Fe, FeO, Fe2O3,
Fe3O4, iron filings, CaCO3, Ca(OH)2, CaCO3.MgO,
silica alumina, china clay, kaolinite, bauxite, emathlite, attapulgite,
coal ash, egg shells, organic salts (such as calcium magnesium acetate
(CMA), calcium acetate (CA), calcium formate (CF), calcium benzoate (CB),
calcium propionate (CP) and magnesium acetate (MA)) and
Ca-montmorillonite.

[0095] The first conditioner 755A can further be configured to deliver the
conditioned waste stream and additives to a first densifier 731A. The
first densifier 731A can be any suitable device configured to encapsulate
at least a portion of the sorbent 790 within the plastics. For example,
in some embodiments, the first densifier 731A can be an extrusion device
configured to apply a relatively high pressure (e.g., compress) to the
plastics and the sorbent 790 such that the sorbent 790 becomes evenly
distributed (e.g., substantially homogenous) and/or encapsulated within
the plastics. Furthermore, the first densifier 731A can be configured to
produce a densified intermediate material. The densified intermediate
material can be in the form of cubes, briquettes, pellets, honeycomb, or
other suitable shapes and forms. In some embodiments, the densified
intermediate material can be used as an engineered fuel feed stock in,
for example, combustion power plants (e.g., coal burning power plants).
In other embodiments, the densified intermediate material can be returned
to the first conditioner 755A such as to further incorporate the sorbent
790 (e.g., raise the sorbent 790 content and/or rigidity within the
pellet). With the desired amount of sorbent 790 encapsulated within the
plastics, a blower 770 can deliver the densified intermediate material
from the first densifier 731A to a first pulverizer 733A.

[0096] The first pulverizer 733A can be any suitable device configured to
reduce the densified intermediate material (e.g., pellets) to a
relatively fine powder, such as about 3/32'' or 1/16''. With the
densified intermediate material pulverized, a blower 770 can deliver the
pulverized material to a third conditioner 755C. In some embodiments, the
third conditioner 755C can be substantially similar to the first
conditioner 755A. Furthermore, the system 700 includes a second mixer
754B configured to deliver a second waste stream from the material
classification subsystem 720. In some embodiments, the second mixer 754B
can be configured to mix a portion of soft plastics with a portion of
fibers. In other embodiments, the second mixer 754B is configured to only
mix soft plastics or fibers with the pulverized material. In this manner,
the third conditioner 755C is configured to condition (e.g., heating,
humidifying, and adding solutions) the pulverized material and the soft
plastics and/or fibers and deliver the conditioned materials to the
second densifier 731B.

[0097] In some embodiments, the second densifier 731B can be any suitable
densifier. In some embodiments, the second densifier 731B can be
substantially similar to the first densifier 731A. For example, in some
embodiments, the second densifier 73113 can be an extrusion device
configured to apply a relatively high pressure to the materials such that
the pulverized intermediate material (i.e. encapsulated sorbent and
plastics) becomes encapsulated in the waste material (e.g., soft
plastics, and/or fibers). In this manner, the second densifier 711B can
be configured to produce an engineered fuel feed stock. In some
embodiments, the fuel feed stock can be returned to the second
conditioner 755A such as to further incorporate the soft plastics and/or
fibers or increase the pellets rigidity. This recirculation may be
especially necessary during the startup process of the production when
the densifier is cool. With the desired amount of sorbent 790
encapsulated within the waste material (e.g., hard plastics, soft
plastics, and/or fibers) a blower 770 can deliver the fuel feed stock
from the second densifier 731B to a first pellet bunker 761. Expanding
further, in some embodiments, the second densifier 731B can be configured
to densify the material into an engineered fuel pellet. In some
embodiments, the engineered fuel pellets can be stored in the first
pellet bunker 761.

[0098] In some embodiments, it can be desirable to reduce the size of the
engineered fuel pellets. In such embodiments, the blower 770 can be
configured to deliver the engineered fuel pellets to a granulator 732. In
this manner, the granulator 732 can reduce the size of the engineered
fuel pellets and produce a granulated fuel feed stock. The granulated
fuel feed stock can have an average particle size in the range of about
0.04-0.2 inches for fluidized bed applications and in the range of about
0.2-0.6 inches for circulating bed application. In some embodiments, the
granulated fuel feed stock can be delivered to a granulated fuel bunker
763, as shown in FIG. 7. In other embodiments, it can be desirable to
further reduce the size of the granulated fuel feed stock. In such
embodiments, a blower 770 can deliver the granulated fuel feed stock to a
second pulverizer 73313. In this manner, the second pulverizer 733B can
reduce the size of the granulated fuel feed stock to a relatively fine
fuel stock. The pulverized fuel feed stock can have an average particle
size in the range of about 0.004-0.12 inches. Furthermore, a blower 770
can be configured to deliver the fuel stock powder to a powdered fuel
bunker 765. Therefore, the system 700 can be configured to produce an
engineered fuel feed stock for a variety of conditions (e.g., the
pelletized fuel stock, the granulated fuel stock, and/or the pulverized
fuel stock).

[0099]FIG. 8 is a schematic illustration of a system 800 for producing an
engineered fuel feed stock from solid waste material. The system 800
includes a separation subsystem 815 and a fuel feed stock production
subsystem 880 (also referred to herein as "Advanced Product
Manufacturing" (APM) 880), The separation subsystem 815 can be
substantially similar to the separation subsystem 715 described above
with respect to FIG. 7. Similarly, the APM 880 can include similar
components as the APM 780. Therefore, certain components of the APM 880
are not described in detail herein and should be considered substantially
similar to the corresponding component of the APM 780 unless explicitly
described as different.

[0100] As shown in FIG. 8, the separation subsystem 815 can be configured
to separate the constituents of a waste stream. In this manner, the
separation subsystem 815 can include a set of bunkers configured to
store, for example, hard plastics, soft plastics, mixed plastics, fibers,
and additives (e.g., any of the additives described above). In this
manner, at least a portion of the waste stream can be delivered to the
APM subsystem 880 to produce an engineered fuel feed stock. Expanding
further, in some embodiments, the separation subsystem 815 can be
configured to deliver a given quantity of the hard plastics, soft
plastics, mixed plastics, and/or additives to the EF subsystem 880. In
such embodiments, the plastics (e.g., the hard and soft plastics) and the
additives are passed through metering devices 875 configured to control
the amount of the hard plastic, soft plastic, and/or additive to be added
to a first mixer 854A. The first mixer 854A can be any suitable device
such as a paddled continuous mixer, a rotary continuous mixer, a screw
conveyor, an auger conveyor mixer, a mechanically vibrating mixer, and/or
an agitating mixer. In this manner, the first mixer 854A can mix the hard
plastics, the soft plastics, and the additives and deliver the plastics
and additives to a pre-treatment mechanism 856.

[0101] The pre-treatment mechanism 856 can be any suitable pre-treatment
mechanism such as, for example, the pre-treatment mechanism 756 described
above. The system 800 further includes a second mixer 854B configured to
receive the treated plastics and additives. Moreover, the separation
subsystem 815 can be configured to deliver a portion of fibers to the
second mixer 854B such that the fibers are mixed with the treated
plastics and additives. In this manner, a mixed waste stream (e.g.,
including the treated plastics and additives and the fibers) can be
delivered to a conditioner 855, as further described herein.

[0102] The conditioner 855 can be any suitable device and/or system
configured to condition at least a portion of the waste stream for
engineered fuel feed stock production. For example, in some embodiments,
the conditioner 855 can be configured to increase the temperature of the
constituents of the waste stream (e.g., the fiber and the capsulated
plastics/sorbent). In some embodiments, the conditioner 855 can be
configured to increase the moisture of the constituents of the waste
stream.

[0103] The conditioner 855 can further be configured to deliver the
conditioned waste stream and additives to a densifier 831. The densifier
831 can be any suitable device configured to encapsulate at least a
portion of the additives into the plastics and fibers. For example, in
some embodiments, the densifier 831 can be an extrusion device configured
to apply a relatively high pressure (e.g., compress) to the mixture
(e.g., plastics, fibers, and additives) such that the additives become
evenly distributed (e.g., substantially homogenous) and/or encapsulated
within the plastics and fibers. Furthermore, the densifier 831 can be
configured to produce a densified intermediate material. The densified
intermediate material can be in the form of cubes, briquettes, pellets,
honeycomb, or other suitable shapes and forms. In some embodiments, the
densified intermediate material can be used as an engineered fuel feed
stock in, for example, combustion power plants (e.g., coal burning power
plants). In other embodiments, the densified intermediate material can be
returned to the conditioner 855 such as to further incorporate the
additives and/or fibers. With the desired ratio of plastics, additives,
and fibers produced a blower 870 can deliver a portion of the densified
intermediate material from a bunker 861 for storage.

[0104] In some embodiments, it can be desirable to reduce the size of the
intermediate material. In such embodiments, the blower 870 can be
configured to deliver the engineered fuel pellets to a granulator 832. In
this manner, the granulator 832 can reduce the size of the engineered
fuel pellets and produce a granulated fuel feed stock. In some
embodiments, the granulated fuel feed stock can be delivered to a
granulated fuel bunker 863, as shown in FIG. 8. In other embodiments, it
can be desirable to further reduce the size of the granulated fuel feed
stock. In such embodiments, a blower 870 can deliver the granulated fuel
feed stock to a pulverizer 833. In this manner, the pulverizer 833 can
reduce the size of the granulated fuel feed stock to a relatively fine
fuel stock. Furthermore, a blower 870 can be configured to deliver the
fuel stock powder to a powdered fuel bunker 865. Therefore, the system
800 can be configured to produce an engineered fuel feed stock for a
variety of conditions (e.g., the pelletized fuel stock, the granulated
fuel stock, and/or the pulverized fuel stock).

[0105] As described above with reference to FIGS. 7 and 8, the engineered
fuel feed stock can contain any suitable ratio of sorbent. For example,
FIG. 9 shows an engineered fuel feed stock in various configurations.
More specifically, a pelletized fuel stock 962A includes 40% hard plastic
and 60% sorbent. In some embodiments, a pelletized fuel stock 9629
includes 30% hard plastic and 70% sorbent. In some embodiments, a
pelletized fuel stock 962C includes 20% hard plastic and 80% sorbent. In
some embodiments, a pelletized fuel stock 962D includes 56% fiber, 14%
hard plastic and 30% sorbent. In some embodiments, an engineered fuel
feed stock includes about 5-50% sorbent and about 50-95% combustible
material (i.e., fibers and plastics). The combustible material typically
includes about 60-80% fiber and about 24-40% plastics. While shown in
FIG. 9 as including specific ratios, in some embodiments, an engineered
fuel feed stock can be include any sorbent-material ratio and/or
configuration.

[0106] As described herein, in some embodiments, a first waste stream can
be combined with an additive material. The first waste stream can include
hard plastic, soft plastic, or a mixed plastic material. For example, the
first waste stream can be substantially all hard plastic. In some
embodiments, the first waste stream includes at least about 80 wt. %, 90
wt. %, or 95 wt, % hard plastic. In some embodiments, the first waste
stream or can include less than about 40 wt. %, 30 wt. %, 20 wt, %, 10
wt. %, or 5 wt, % soft plastic. In some embodiments, the first waste
stream includes less than about 20 wt. %, 10 wt. %, or 5 wt, % fibers, In
some embodiments, the first waste stream includes less than about 20 wt.
%, 10 wt. %, or 5 wt. % soft plastic and fiber in combination. In some
embodiments, the first waste stream is substantially free from glass,
metals, grit, and noncombustibles.

[0108] As described herein, in some embodiments, the combined first waste
stream and additive can be combined with a second and/or third waste
stream to form an engineered fuel feed stock. For example, the second
waste stream can include hard plastic, soft plastic, or mixed plastic and
the third waste stream can include fibers. In some embodiments, the
second waste stream includes plastics and fibers. In sonic embodiments,
the second waste stream includes less than about 20 wt. %, 10 wt. %, or 5
wt. % hard plastic. In some embodiments, the second waste stream includes
at least about 5 wt. %, 10 wt. %, or 20 wt. % soft plastic. In some
embodiments, the second waste stream includes at least about 80 wt. %, 90
wt. %, or 95 wt. % fibers. In some embodiments, the second waste stream
includes at least about 95 wt. % soft plastic and fibers in combination.
In some embodiments, the second waste stream is substantially free from
glass, metals, grit, and noncombustibles. In some embodiments, the final
engineered fuel feed stock can have a bulk density of between about 10
lb/ft3 and about 60 lb/ft3. In some embodiments, the final
engineered fuel feed stock can have a bulk density of between about 20
lb/ft3 and about 40 lb/ft3.

[0109] As described herein, during the separation and classification
process, various components of the waste streams can be shredded with a
primary shredder and optionally a secondary shredder. In some
embodiments, the hard plastic component of the waste stream has an
average particle size of less than about 1/2 inch, 3/8 inch, 1/4 inch,
3/16 inch, 1/8 inch or 3/32 inch. In some embodiments, the hard plastic
component of the waste stream has an average particle size in the range
between about 3/32 inch and about 1/4 inch. In some embodiments, the hard
plastic component of the waste stream has an average particle size in the
range between about 3/32 inch and about 3/8 inch. In some embodiments,
the hard plastic and soft plastic components of the waste stream have an
average particle size in the range between about 3/32 inch and about 3/4
inch. In some embodiments, the soft plastic component of the waste stream
has an average particle size in the range between about 1/8 inch and
about 3/8 inch. In some embodiments, the fiber component of the waste
stream has an average particle size in the range between about 1/8 inch
and about 3/8 inch. In some embodiments, the fiber and soft plastic
components of the waste stream have an average particle size in the range
between about 1/8 inch and about 3/8 inch.

[0110] In some embodiments, the waste streams or individual components of
the waste stream are conditioned one more times during the engineered
fuel feed stock production process. For example, the conditioning can
include adding heat to raise the temperature of the waste stream, adding
water to raise the raise the moisture content of the waste stream, or
adding steam to raise the temperature and the moisture content of the
waste stream. In some embodiments, the temperature of one or more of the
waste streams can be raised to about 300° F., 325° F.,
350° F., or 375° F. In some embodiments, the moisture
content of one or more of the waste streams can be raised to at least
about 5%, 10% or 15%

[0111] As described herein, one or more waste streams can be combined with
an additive and then compressed to form a densified engineered fuel feed
stock in a single pass (see, e.g., FIG. 8), or one or more waste streams
can be combined with an additive and then compressed to form a densified
intermediate material, ground, and then combined with additional waste
streams before being compressed tier second time to form a densified
engineered fuel feed stock (see, e.g., FIG. 7). In some embodiments, the
densified intermediate material and/or the densified engineered fuel feed
stock can be ground (e.g., granulated or pulverized) to an average
particle size of less than about 3/4 inch, 5/8 inch, 1/2 inch, 3/8 inch,
1/4 inch, 3/16 inch, 1/8 inch, 3/32 inch.

[0112] As described herein, an engineered fuel feed stock made from a
processed MSW waste stream can include a hard plastic content of between
about 0 wt. % and about 40 wt. %, a soft plastic content of between about
0 wt. % and about 40 wt. %, a fiber content of between about 30 wt. % and
about 80 wt, %, and a sorbent content of between about 5 wt. % and about
50 wt. %. In some embodiments, the hard plastic content is between about
0 wt. % and about 20 wt. %, between about 5 wt. and about 20 wt, %,
between about 10 wt. % and about 20 wt. %, between about 5 wt. % and
about 15 wt. %, or between about 10 wt. % and about 15 wt. %. In sonic
embodiments, the soft plastic content is between about 0 wt. % and about
20 wt, %, between about 5 wt. % and about 20 wt. %, between about 10 wt.
% and about 20 wt. %, between about 5 wt. % and about 15 wt. %, or
between about 10 wt, % and about 15 wt. %. In some embodiments, the fiber
content is between about 30 wt. % and about 60 wt. %, between about 40
wt. % and about 60 wt. %, or between about 40 wt. % and about 50 wt. %.
In some embodiments, the sorbent content is between about 10 wt. % and
about 40 wt. %, between about 20 wt. % and about 40 wt. %, or between
about 30 wt. % and about 40 wt. %.

[0113] As described herein, an engineered fuel feed stock made from a
processed MSW waste stream can include a mixed-plastic content of between
about 10 wt. % and about 40 wt. %, a fiber content of between about 30
wt. % and about 80 wt. %, and a sorbent content of between about 5 wt. %
and about 50 wt. %. In some embodiments, the mixed-plastic content is
between about 0 wt. % and about 20 wt. %, between about 5 wt. % and about
20 wt. %, between about 10 wt. % and about 20 wt. %, between about 5 wt.
% and about 15 wt. %, or between about 10 wt. % and about 15 wt. %. In
some embodiments, the fiber content is between about 30 wt. % and about
60 wt. %, between about 40 wt. % and about 60 wt. %, or between about 40
wt. % and about 50 wt. %. In some embodiments, the sorbent content is
between about 10 wt. % and about 40 wt. %, between about 20 wt. % and
about 40 wt. %, or between about 30 wt. % and about 40 wt. %.

EXAMPLES

[0114] By way of example, a fuel production process can include passing a
waste stream (e.g., hard plastics, soft plastics, and/or fibers) and
additives (e.g., sorbents, biomass, biomaterials, and/or the like)
through a densifier any number of times to incorporate the additive into
waste material. Passing the waste stream/additive mixture through the
densifier multiple times increases the temperature of the constituents to
facilitate incorporation of the additive into the waste material
constituents.

[0115] For example, approximately 20 wt. % of hard plastic and 80 wt. % of
sorbent (e.g., hydrated lime) were mixed and passed through a pelletizer
10 times to produce densified pellets of hard plastic and sorbent in
order to observe the variation in physical properties of the hard plastic
and/or sorbent, and determine the required temperature to produce
satisfactory fuel pellets. As indicated by the arrows NN and OO in FIG.
10, the mixture of the hard plastic and sorbent are shown after a first,
second, third, fourth, fifth, sixth, seventh, eighth, ninth, and tenth
pass through the pelletizer. As shown, the sorbent, which is a white
powdery substance, is gradually incorporated after each pass through the
pelletizer. As described above, the temperature of the mixture increases
with each pass through the pelletizer, thus, altering the physical
properties of the hard plastic and/or sorbent Table 1 below illustrates
the temperature increase after each pass through a densifier:

[0116] As shown FIG. 10, the sorbent is eventually incorporated into the
hard plastic after 10 passes through the pelletizer (container in the
lower right of FIG. 10). Although the process is shown and described in
this example as including 10 passes through a pelletizer, the process can
include more or fewer passes through a pelletizer or densifier. For
example, the engineered fuel production process can include conditioners
as described above to raise the temperature of the mixture prior to
densification. In other examples, the sorbent can be selected to generate
heat when mixed with the waste materials and/or waiter (e.g., quick
lime).

[0117] The hard plastic pellets containing the sorbent (intermediate
material) were then passed through a granulator to reduce the size of the
engineered fuel pellets and produce a granulated fuel feed stock having
an average particle size in the range of about 0.004-0.04 inches. The
granulated intermediate material (37.5 wt. % of total) was mixed with 6.5
wt. plastic and 56 wt. % fibers and passed through a pelletizer 10 times
to produce densified pellets of engineered fuel feed stock containing 1.4
wt. % plastic, 56 wt. % fiber and 30 wt. % sorbent. FIG. 11 illustrates
the mixture of the intermediate material (hard plastic and sorbent), soft
plastic and, fiber after a first, second, third, fourth, fifth, sixth,
seventh, eighth, ninth, and tenth pass through a pelletizer (as indicated
by the arrows PP and QQ) to form densified pellets of engineered fuel
feed stock. The engineered fuel pellets can be used in the pellet form,
passed through a granulator to reduce the size of the engineered fuel
pellets and produce a granulated fuel feed stock having an average
particle size of about 0.04 inches or in the range of about 0.008-0.12
inches, or passed through a pulverizer to reduce the size of the fuel
feed stock to a relatively fine fuel stock having an average particle
size of about 0.02 inches or in the range of about 0.008-0.08 inches.

[0118] While various embodiments have been described above, it should be
understood that they have been presented by way of example only, and not
limitation. Where methods described above indicate certain events
occurring in certain order, the ordering of certain events may be
modified. Additionally, certain of the events may be performed
concurrently in a parallel process when possible, as well as performed
sequentially as described above.

[0119] Where schematics and/or embodiments described above indicate
certain components arranged in certain orientations or positions, the
arrangement of components may be modified. Similarly, where methods
and/or events described above indicate certain events and/or procedures
occurring in certain order, the ordering of certain events and/or
procedures may be modified. While the embodiments have been particularly
shown and described, it will be understood that various changes in form
and details may be made.

[0120] For example in reference to FIG. 7, while specific waste streams
are described as entering the first mixer 754A and the second mixer 754B,
the waste streams can be introduced to the first mixer 754A or second
mixer 754B in any given configuration. For example, in some embodiments,
the first mixer 754A can be configured to receive only hard plastics,
only soft plastics, and/or any suitable combination of hard plastics and
soft plastics. Similarly, in some embodiments, the second mixer 755B can
be configured to receive only soft plastics, only fibers, and/or any
suitable combination of soft plastics and fibers. Furthermore, the any
constituent configuration of the first mixer 754A can be used with any
constituent configuration of the second mixer 754B.

[0121] Although various embodiments have been described as having
particular features and/or combinations of components, other embodiments
are possible having a combination of any features and/or components from
any of embodiments as discussed above.